In order to control the idle speed of an internal combusion engine, it has been common to utilize various types of devices which function to form a stop for the throttle. Such devices have been commonly known as throttle kickers and are shown, for example, in U.S. Pat. Nos. 3,730,153, 3,760,785 and 4,056,082. The devices have been commonly electrically energized solenoids or vacuum actuated diaphragm devices or combinations of the two. In such devices combining a solenoid and a vacuum actuated device, the devices may not have been capable of an anti-dieseling function because when the solenoid is de-energized, vacuum continues to maintain the stem of the device so that the stem cannot return to its original position unless provision is made for relieving the vacuum quickly.
Another problem of the combined type of throttle positioning device has been that the solenoid must have sufficient force to overcome the hysteresis of the vacuum device and the friction of the seals.
In devices utilizing a magnetic stop for the solenoid plunger it is desirable to be able to vary the portion of the magnetic stop.
In accordance with the invention, the positioning device comprises a solenoid having a plunger slidable upon energization of the solenoid, a solenoid stop associated with the solenoid, a stem operatively connected to said plunger, a motor connected to the solenoid stop and operable to move the stop to selected positions, such that when the solenoid is energized, the plunger is moved to engage the stop and move the stem to a predetermined position, the extent of movement being determined by actuation of the motor to move the stop in predetermined positions.